Loose course attachment for knitting machines



April 1961 P. A. MAHLER ETAL 2,981,085

LOOSE COURSE ATTACHMENT FOR KNITTING MACHINES Filed April 23, 1957 3 Sheets-Sheet 1 A ril 25, 1961 P. A. MAHLER ET AL 2,981,085

LOOSE COURSE ATTACHMENT FOR KNITTING MACHINES Filed April 25,1957

3 Sheet April 1961 P. A. MAHLER ET AL 2,981,085

LOOSE COURSE ATTACHMENT FOR KNITTING MACHINES 3 Sheets-Sheet 3 Filed April 25, 1957 United States Patent 2,981,085 7 LoosE COURSE ATTACHMENT FOR KNITTING MACHINES Filed Apr. 23, 1957, Ser. No. 654,534

6 Claims. (CI. 66-54) This invention relates to an improved loose course mechanism for circular knitting machines, more particularly stocking machines, of the class comprising a pattern drum for controlling sequential operations of the machine and a pattern chain for controlling the intermittent rotary movement of the drum.

A principal object of the invention is to provide in a machine of this class a relatively uncomplicated loose course mechanism affording precise location of the loose course in the stocking or other fabric and having a high degree of flexibility as to choice of location for said course or courses.

Another object is to provide a loose course mechanism the control of which is divorced from the pattern cylinder.

The invention resides also in certain mechanical details and devices hereinafter described including a novel means for regulating the extent of the loose course.

In the attached drawings:

Fig. l is a view in perspective of the parts of a circular knitting machine immediately involved in and including the loose course mechanism of the present invention;

Fig. 2 is a side elevational view of the portion of the machine shown in Fig. 1;

Fig. 3 is a fragmentary cross sectional view on an enlarged scale showing a detail of the loose course mechanism;

Fig. 4 is a fragmentary perspective view on enlarged scale showing a detail of the pattern chain;

Fig. 5 is a fragmentary enlarged side view of the upper part of the mechanism shown in Fig. 2; i

Fig. 6 is a fragmentary inner face view on enlarged.

scale of the cylinder cam ring of the machine;

Fig. 7 is a sectional view on the line 7-7, Fig. 6, and

Fig. 8 is an enlarged fragmentary sectional view of the upper portion of Fig. 7.

With reference to the drawings, 1 is the needle cylinder of a rotary cylinder circular knitting machine; 2

e is a conventional pattern drum which controls various recurrent operations of the machine; and 3 is the pattern chain which controls the intermittent rotary movement of the drum in well known manner. A machine of this type is disclosed for example in United States Patent No. 2,422,568. The drum is mounted on a shaft 4 and is intermittently rotated or indexed by a pawl 5 which acts on a ratchet wheel 6 attached to the drum. The pawl is oscillated continuously in predetermined timed relation with the needle cylinder 1 through a bell crank lever 7 on rock shaft 8, the pawl being pivot-ally attached at 9 to one arm 11 of the lever.

The chain 3 engages a sprocket 12 journaled on the shaft 4, and the sprocket is rotated intermittently by a pawl 13 pivotally mounted on a pin 14 extending axially from the second arm 15 ofbell crank lever 7. PaWl 13 drives a ratchet wheel 16 attached to sprocket 12. The chain has lugs or earns 17 which co-act with a finger 18 on an arm 19 of a lever 21 pivotally supported on a relatively fixed shaft 22. The lever 21 has an arm 23 which, when the lever is in the normal position shownin the drawings, engages and lifts the pawl 5 from ratchet wheel 6 so that the continuing oscillations of the pawl are inoperative to advance the wheel and drum. When so lifted the end of the pawl rides on the cam like edge 24 of the arm. When the finger 18 is engaged by one of the chain cams 17 the lever 21 is oscillated counter clockwise as viewed in Figs. 1 and 2 to allow pawl 5 to engage the ratchet wheel 6 and to index the pattern drum 2.

In accordance with the present invention a rod 25 is pivotally attached at one end of the arm 15 of lever 7. As the lever oscillates it rocks a stitch cam-adjusting element in the form of a second bell crank lever 26 about a relatively fixed axis in a shaft 27, the rod 25 being pivotally connected to one arm 28 of the last named lever. The other arm 29 of the lever carries a pin 31 which occupies an arcuate slot 32 in a transmission lever or arm 33, this arm being pivotally attached at 34 to cam disc 35 mounted on a fixed pivot 36 on the machine frame 37. When the arm 33 is supported in the position shown in Figs. 1 and 2' the slot 32 is concentric with the shaft 27 so that pin 31 may move freely in the slot as the lever 26 oscillates in synchronism with the pattern chain Without affecting the position of the arm. Thus, these elements constitute a normally disengaged clutch. The aim is supported in this idle position by a lever 38 supported on a fixed pivot 39 and arranged so that its upper end 41 may underlie the arm 33. The lower end of the lever is supported by a second lever 42 pivoted at 43 on the frame 37 and having a depending finger 44 whose lower end normally rides on a peripheral surface 45 of sprocket 12 and projects between the sprocket teeth 46 and ratchet wheel 16 as best shown in'Fig. 3. When the finger 44 thus rides on surface 45 the lever 38 is in position to support arm 33 as described above. A spring 47 holds the lower end of lever 38 securely in contact with lever 42, and the finger 44 on surface 45.

The chain 3 carries pins 48 at predetermined intervals and these pins project from the inner side of the chain toward the surface 45 in position to engage the inclined edge 49 of finger 44 as the chain is traversed by pawl 13. Such engagement elevates the finger and lifts the lever 42 and with it the lower end of lever 38. The upper end of this lever is then depressed withdrawing its support of lever 33 and transferring its support to pin 31. This causes a shoulder '51 at the upper edge of slot 32, normally held out of the oscillatory path of pin 31' to move into the path of the latter as it moves to the right, see Fig. 5, thereby coupling the adjusting element 26 to the transmission lever 33 so that the pin then functions to shift the arm longitudinally to the right which turns the cam disc 35 counter clockwise as indicated by the arrow in Fig. 5 Thus, when a pin 48 of chain 3 engages and elevates finger 44 the clutch is engaged and the cam disc 35 will be actuated as described.

The arm 33 has an offset strap 52 attached to one face thereof as a guide for the upper end of a rod 53,

the lower end of the rod being pivotally attached to the arm 11 of lever 7. An edge of rod 53 is held in contact with a collar 54 on shaft 27 by a spring 55, the collar thereby also guiding the rod in its longitudinal reciprocatory movement in response to the oscillations of lever 7. When the arm 33 is in the normal position shown in Figs. 1 and 2, the rod 53 slides freely "through strap 52. When the arm is in the position to which it is advanced by pin 31 acting against shoulder 51 as described above, an upward movement of the rod 53 will bring a shoulder 56 on the rod into engagement with a pin 57 at one end of the strap and will elevate the arm 33 to clear the shoulder 51 from pin 31 to uncouple the adjusting element 26 from the transmission arm 33, the arm 33 then being free to move to the left as viewed in the drawings independently of lever 26 until the pin meets the right hand end of the slot 32. Such free movement of the arm will, under circumstances described below, take place by action of a spring 58 connected to cam disc 35 and tending to return the disc by clockwise rotation to its original position after angular displacement by arm 33 as described above. It will be noted that rod 53 is adjustable in length through medium of an adjustable tip 59.

The normal position of disc 35 is determined by spring 58 and a stop pin 61 which extends into a recess 62 in the disc for abutment with a shoulder 63 to limit clockwise displacement of the disc by spring 58 as shown in Fig. 2. The disc has a coaxial shoulder 64 on which a cam element 65 is seated, the said element being secured to the face of the disc by a screw 66. The aperture provided in cam element 65 for screw 66 is slotted to permit limited adjustment of the element circumferentially of the disc on shoulder 64. An adjustable set screw 67 in one end of a lever arm 68 is arranged for seating engagement with the peripheral surface of cam 65. When the arm 33 is in the normal elevated position, as in Fig. 1, the screw 67 engages the inclined face 69 of the cam. When the disc 35 is turned counter-clockwise the screw with the corresponding end of lever arm 68 is moved upwardly, the screw eventually seating on the top surface 71 of the cam which describes a circle concentric with its carrier disc. After the screw passes off of the inclined cam face 69 further rotation of the disc does not alter the position of lever arm 68 until a reverse movement of the disc brings face 69 again into contact with the screw.

The opposite end 72 of lever 68 seats against the head of a pin 73 which is slidably fitted to an axial bore 74 in a screw 75 in the cylinder cam ring 76, see Figs. 6-8. The lower end of screw 75 extends into the upper end of a vertical guide way 77 in the inner face of the ring and the screw is adjustable to determine the extent to which the end of the screw projects into the guide way. A slide member 78 is fitted to the guide way and is held in place in the latter by a bolt 79 which extends through the slide and through a slot 81 in the rear wall of the guide way and is secured by nuts 82 seating against a washer 83 bearing slidably against the rear face of said wall. The bolt also secures cylinder needle stitch cam 8-4 to the front face of the slide. A second bolt 85 similarly retains the lower end of slide 78 in the guide way for adjustment vertically in the latter. A spring 86 at the bottom of the slide tends to hold the slide in a normal elevated position against the bottom of screw 75. The pin 73 seats on the upper end of slide 78 and is confined without play between the slide and the end 72 of lever arm 68. When the latter arm is oscillated by counter clockwise rotation of cam disc 35 as described above the slide 78 and with it cam 84 is depressed to an accurately predetermined extent. Return of cam disc 35 to normal position permits spring 86 to re-elevate slide 78.

In its normal relatively elevated position the cam 84 actuates the cylinder needles in conventional manner to form the normal knitted loops. The path of the needle butts in this case is indicated at 87. When the slide and cam are depressed the needles are forced to take a lower course indicated at 88 with the result that the length of the knitted loops are abnormally long and form a loose course or courses in the fabric.

It is evident that the extent of this loose course i.e. the number of consecutive loops embraced therein, will be a function of the dwell of screw 67 on the top surface 71 of cam element 65. Following actuation of the said element by arm 33 as described above, the reverse or clockwise movement of the bell crank 7 will have the effect of moving the pin 31 to the left. This will free the arm 33 and permit spring 58 to turn disc 35 clockwise so that the arm 33 moves to the left with pin 31 and at the same rate with the pin still engaged with shoulder 51 as shown in Fig. 5. Also, the rod 53 will now move upwardly, and the shoulder 56 will eventually engage pin 57 on arm 33 and will elevate that arm to an extent clearing shoulder 51 from pin 31. At this point spring 58 takes over to return cam disc 35 to its normal position and to thereby release cam slide 78 so as to permit spring 86 to return cam 84 to the normal elevated position terminating the loose course.

The extent or length of the loose course can be regulated by adjusting the tip 59 on rod 53. This will have the effect of changing the point in the return movement (to the left) of arm 33 at which the shoulder 56 engages pin 57 to release shoulder 51 from pin 31, and will thereby increase or decrease the period of dwell of screw 67 on cam surface 71, as the case may be.

The mechanism described provides for formation in the fabric at any point or points desired of a loose course of variable length, as may be required, under control directly of the chain 3 and independently of the drum 2, leaving the latter free for control of other machine functions.

We claim:

1. In a knitting machine comprising a rotary cylinder, needles in said cylinder, a cam for actuating the needles to form yarn into inter-knitted loops and adjustable to vary the length of said loops, a pattern drum for con trolling operations of the machine and means for indexing the drum, a pattern chain having cams controlling the actuations of the drum indexing means and mechanism for indexing the chain in timed relation to the rotary movements of the cylinder, and mechanism for adjusting the needle cam including a primary actuating element movable in synchronism with the chain indexing mechanism, transmission means for operatively interconnecting said actuating element with the cam needle, means for normally uncoupling the actuating element from the transmission means and means responsive to the movements of the chain for intermittently coupling the actuating element to the transmission means.

2. In a knitting machine comprising a rotary cylinder, needles in said cylinder, a cam for actuating the needles to form yarn into inter-knitted loops and adjustable to vary the length of said loops, a pattern member movable in synchronism with the rotary movements of the cylinder, a cam adjusting element movable in synchronism with said member, transmission means for operatively connecting said element with the cam, means selectively controlled by the pattern member for coupling the adjusting element to the transmission means, and means operable independently of said pattern member for uncoupling said element from the transmission means.

3. In a knitting machine comprising a rotary cylinder, needles in said cylinder, a cam for actuating the needles to form yarn into interknitted loops and adjustable to vary the length of said loops, a pattern member movable in synchronism with the rotary movements of the cylinder, a cam adjusting element movable in synchronism with said member, transmission means including a normally disengaged clutch for operatively connecting said element with the cam, means actuated by the pattern member for engaging the clutch to connect the said element with the cam, and means operated in timed relation with the pattern member for subsequently disengaging the clutch.

4. A knitting machine according to claim 3 including adjustable means for varying the period elapsing between engagement and succeeding disengagement of the clutch.

5. A knitting machine according to claim 4 wherein the clutch comprise a transmission member selectively engageable with and disengageable from the cam adjusting element, and means for normally retaining the transmission member in the disengaged position, said means actuated by the pattern member being operable after actuation thereof to retract the retaining means to permit the transmission member tomove to the engaged position, said disengaging means being operable apart from said retaining means for subsequently returning the member to the disengaged position.

6. In a knitting machine comprising a rotary cylinder, needles in said cylinder, a cam for actuating the needles to form yarn into interknitted loops and adjustable to vary the length of said loops, an intermittently traversible pattern member having a ratchet, a bell crank lever oscillating in timed relation with the rotary movements of the cylinder, a pawl on one arm of said lever operatively engaged with the ratchet to traverse the pattern member,

a cam adjusting element operatively connected to the said arm for movement with the latter, transmission means including a normally disengaged clutch for operatively connecting said element with the cam, means actuated by the pattern member for engaging the clutch to connect the adjusting element with the cam, and means connected with the other arm of the bell crank lever for subsequently disengaging the clutch.

References Cited in the file of this patent UNITED STATES PATENTS 404,930 Pepper et al June ll, 1889 1,147,730 lngalls July 27, 1915 2,573,782 Zeruneith Nov. 6, 1951 2,576,962 McDonough Dec. 4, 1951 2,664,723 McDonough Jan. 5, 1954 

